KR101509994B1 - Oil Pressure Engaging type Variable Displacement Oil Pump - Google Patents

Abstract

An oil pressure engaging type variable displacement oil pump of the present invention comprises: a pair of a primary chamber and a secondary chamber where engine oil pumped by the rotation of a rotor (5) flows in through respectively while being installed in an inner space of a pump housing (3); and a bypass valve (50) allowing the engine oil to flow into the primary chamber and discharging the engine oil from the secondary chamber (20) when the pressure of the engine oil is 4 bar. Therefore, a reduction rate of engine drive torque is relatively lowered significantly by oil pressure in a relationship of ′flow rate x oil pressure′ which is a major factor in the loss of an oil pump, and a fuel efficiency improvement rate is especially enhanced largely as much as the lowered amount of the reduction rate of the engine drive torque.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a variable pressure oil pump,

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a variable oil pump, and more particularly, to an oil pressure interlocking type variable oil pump in which a fuel efficiency improvement rate is greatly increased by expanding an operation range for preventing drive torque loss of an engine by changing pumping volume in multiple stages using engine oil pressure .

Generally, engine oil is circulated in an engine of a vehicle to prevent overheating of the engine and reduce frictional force between various engine sections. For this purpose, an oil pump is applied.

However, since the oil pump is operated to discharge the flow rate to the discharge side and to suck the flow rate returned to the suction side, the driving torque of the engine is inevitably lost at the time of operating the oil pump.

Since the improvement of the driving torque of the engine in the vehicle is essential for improving the fuel efficiency, the driving torque loss due to the oil pump proportional to the relation of the flow rate and the oil pressure of the oil pump (the consumed horsepower consumed for discharging the oil) Performance can be reduced.

In recent years, fuel efficiency has become more important due to global oil price and CO ₂ regulations. Particularly, considering improvement of the driving torque of the engine is an essential factor for improving the fuel efficiency, reduction of the driving torque loss by the oil pump can be very effective for improving the fuel efficiency.

An example of an oil pump for this purpose is a variable oil pump. In a variable oil pump, the pumping volume per unit of rotation is reduced from the high engine rotation speed of the engine, so that when the discharge flow rate is fixed, the drive torque loss can be reduced by reducing the discharge flow rate.

In the fixed oil pump, the consumption volume is linearly increased as the RPM of the engine rises as the pumping volume per unit rotation is constant at the time of oil delivery. However, the variable oil pump reduces the pumping volume per unit of rotation at high speed, This is a way to improve fuel efficiency by reducing fuel consumption.

Korean Patent Publication No. 10-2011-0026086 (Mar. 15, 2011)

However, the reduction of the chamber volume of the variable oil pump depends on the degree of compressive deformation of the spring, and the compression deformation of the spring depends on the engine speed (RPM) for rotating the rotor, (RPM) of the engine.

Therefore, the efficiency of reducing the driving torque due to the hydraulic pressure is relatively neglected in the relation of the "flow quantity x hydraulic pressure", which is the main loss factor of the oil pump, and this is a structural limitation that lowers the fuel efficiency improvement efficiency using the variable oil pump .

In view of the above, the present invention is characterized in that the engine oil pressure is divided into a low pressure and a high pressure regardless of the engine speed (RPM), and the pumping volume is expanded at least at low pressure, The driving range for preventing the loss of the driving torque of the engine is greatly expanded. In particular, in the relation of the " flow rate x hydraulic pressure ", which is a major loss factor of the oil pump, the driving torque reduction rate by the hydraulic pressure is relatively lowered, The present invention provides a variable oil pump with an oil pressure interlocking type.

In order to accomplish the above object, the present invention provides an oil pressure interlocking type variable oil pump comprising: a pair of primary and secondary chambers formed in an inner space of a pump housing, into which engine oil pumped by rotation of a rotor flows; Wherein when the pressure of the engine oil is low, the engine oil flows into the primary chamber and the secondary chamber, respectively, while when the pressure of the engine oil is high, the engine oil is supplied to the primary chamber and the secondary chamber, A bypass valve for discharging the gas from either one of the chambers; Is further included.

The low pressure is an engine oil pressure of 2 bar, the high pressure is an engine oil pressure of 4 bar, and the bypass valve is switched from high pressure to on under the control of the ECU.

The secondary chamber is located in a camming portion where a variable spring is located and the primary chamber is spaced from the secondary chamber at a position delimited by the cam ring and the bypass valve is installed in the secondary chamber.

A main oil line connected to the main gallery of the engine is connected to the primary chamber, and a sub oil line branched from the main oil line is connected to the secondary chamber, and the bypass valve is connected to the secondary chamber, Path oil line.

The bypass valve cuts off the bypass oil line when the ECU is off, opens the bypass oil line when the ECU is on, and the ECU turns off the bypass valve at a low pressure Off) and switches from high pressure to on.

The rotor is rotated by a driving force of the engine, and the rotor is radially engaged with a vane which contacts the inner circumferential surface of the cam ring pushed by the variable springs into the secondary chamber.

The present invention has the effect of significantly increasing the fuel efficiency improvement rate by the oil pump because the reduction rate of the drive torque due to the hydraulic pressure is greatly lowered in relation to the 'flow rate x hydraulic pressure' which is the main loss factor of the oil pump.

Further, the present invention prevents the loss of drive torque of the engine by interlocking with the engine oil pressure regardless of the engine speed (RPM), thereby reducing the drive torque loss and improving the fuel economy improvement compared with the spring compression system interlocked with the engine speed There is an effect of further heightening.

In addition, the present invention can reduce the pumping volume at the high-pressure engine oil pressure while expanding the pumping volume at the low-pressure engine oil pressure regardless of the engine speed (RPM), thereby reducing the driving torque loss of the engine This has the effect of expanding.

Fig. 1 shows a configuration of an oil pressure interlocking variable oil pump according to the present invention, and Fig. 2 shows an oil pressure interlocking variable oil pump according to the present invention interlocked with an engine oil pressure (low pressure (2 bar) to high pressure (4 bar) 3 is a performance diagram of the oil pressure interlocking type variable oil pump according to the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings, which illustrate exemplary embodiments of the present invention. The present invention is not limited to these embodiments.

Fig. 1 shows a configuration of an oil pressure interlocking type variable oil pump according to the present embodiment.

As shown in the figure, the oil pressure interlocking variable oil pump 1 includes a pump housing 3 having a space through which oil is discharged, a rotor 5 to which a vane 6 is coupled, a cam ring 7, a variable spring 9 A pair of chambers 10 and 20 into which the oil sucked in the main gallery 40 flows respectively and a bypass valve 50 for bypassing some oil in the suction oil under the control of the ECU 60.

The pump housing (3) forms an outer shape of the oil pressure interlocking type variable oil pump (1).

As the rotation of the rotor 5 is progressed by engine power, a plurality of vanes 6 arranged in the circumferential direction are brought into contact with the cam ring 7 to adjust the height of the rotor 5, and oil is sucked into the space of the pump housing 3 To form a vacuum pressure that can be applied.

The variable spring 9 pushes the cam ring 7 inside the pump housing 3 and is compressed by the cam ring 7 pushed by the pressure increase of the oil sucked in the main gallery 40. The variable spring 9 is positioned toward the second chamber 20 of the pair of chambers 10, 20.

The pair of chambers 10 and 20 are composed of a primary chamber 10 and a secondary chamber 20 partitioned by a cam ring 7 inside the pump housing 3 and connected to the variable spring 9 The primary chamber 10 is formed at a position opposite to the secondary chamber 20 located at the cam ring 7.

Therefore, the oil pressure interlocking type variable oil pump 1 according to the present embodiment is a two-stage variable oil pump type having two chambers.

A main oil line 30-1 is connected to the primary chamber 10 so that the oil sucked in the main gallery 40 flows into the primary chamber 10 and the oil flowing through the main oil line 30-1 The sub oil line 30-2 branched from the main oil line 30-1 is connected so that some oil is introduced.

A bypass oil line 30-3 is connected to the secondary chamber 20 so that the oil sucked through the sub oil line 30-2 is discharged to the main gallery 40, 30-3 are provided with a bypass valve 50. In this embodiment, the bypass oil line 30-3 may lead to the oil pan.

The bypass valve 50 is turned on / off by the control of the ECU 60 which detects the pressure of the oil sucked in the main gallery 40 so that the oil flowing into the secondary chamber 20 And the secondary chamber 20 is maintained or discharged.

On the other hand, Fig. 2 shows the operating state of the oil pressure interlocking variable oil pump interlocked with the engine oil pressure (low pressure (2 bar) to high pressure (4 bar)).

As shown, when the engine oil is pumped by the rotation of the rotor 5, the ECU 60 determines whether the pressure of the engine oil is low (2 bar) or high (4 bar) While controlling the variable oil pump 1 in the high pressure mode at the high pressure (4 bar).

For example, in the low pressure mode, the ECU 60 blocks the bypass oil line 30-3 connected to the secondary chamber 20 by keeping the bypass valve 50 off. Therefore, the engine oil sucked in the main gallery 40 flows into the primary chamber 10 through the main oil line 30-1, and the secondary oil is supplied to the secondary chamber 20 through the sub oil line 30-2 The engine oil sucked in the main gallery 40 is sucked.

At this time, the camshaft 7 is pressed by the pressure of the engine oil filled in the secondary chamber 20 to compress the variable spring 9, and the compression of the variable spring 9 causes the volume expansion of the secondary chamber 20 Lt; / RTI >

As described above, since the engine oil flows into both the primary chamber 10 and the secondary chamber 20, the variable oil pump 1 can sufficiently supply the flow rate of the engine oil required by the engine.

On the other hand, in the high pressure mode, the ECU 60 opens the bypass oil line 30-3 connected to the secondary chamber 20 by switching the bypass valve 50 on. Therefore, the engine oil flows into both the primary chamber 10 and the secondary chamber 20 in the same manner as in the low-pressure mode, but the engine oil flowing into the secondary chamber 20 flows into the bypass oil line 30-3 It is inevitable to be discharged through.

As a result, the camshaft 7 is pushed by the force exerted by the variable spring 9, and the cam ring 7 is pushed by the force in the secondary chamber 20 20).

In this manner, the engine oil is exhausted from the secondary chamber 20 and flows only into the primary chamber 10, so that the variable oil pump 1 can reduce the pumping volume per unit of rotation in the high-speed condition of the engine.

3, the engine oil discharge of the secondary chamber 20 is continued until the high pressure (4 bar) is reached after starting at the low pressure (2 bar), thereby increasing the engine drive torque reduction rate, The reduction of the consumption horsepower by the torque reduction rate can greatly improve the fuel economy.

For example, the engine drive torque reduction rate of the two-stage variable oil pump (A) is relatively large compared to the fixed oil pump (C) and the one-stage variable oil pump (B) An engine drive torque reduction section K formed between the low pressure (2 bar) and the high pressure (4 bar) with respect to the oil pump B is further formed.

This engine driving torque reduction period K means that the efficiency of reducing the driving torque due to the hydraulic pressure can be relatively increased in the relation of the flow rate x hydraulic pressure, which is the main loss factor of the oil pump.

In this case, the stationary oil pump C is of a type that does not change the pumping volume of the chamber, the one-stage variable oil pump B is a type in which one chamber is formed while the pumping volume is changed, Is an oil pressure interlocking type variable oil pump 1 according to the present embodiment.

As described above, the oil pressure interlocking type variable oil pump 1 according to the present embodiment is provided with a pair of variable oil pumps 1, each of which is formed in the inner space of the pump housing 3 and is pumped by the rotation of the rotor 5 The primary chamber 10 and the secondary chamber 20 and the bypass 20 which discharges the engine oil to the primary chamber 10 while the engine oil is at a pressure of 4 bar, The valve 50 is further included so that the reduction rate of the engine drive torque due to the hydraulic pressure is significantly lowered in relation to the flow rate x hydraulic pressure, which is a major loss factor of the oil pump. Especially, as the engine drive torque reduction rate is lowered, Can be improved.

1: variable oil pump 3: pump housing
5: rotor 6: vane
7: Camming 9: Variable spring
10: primary chamber 20: secondary chamber
30-1: Main oil line 30-2: Sub oil line
30-3: Bypass Oil Line 40: Main Gallery
50: bypass valve 60: ECU (Engine Control Unit)

Claims (6)

A pair of primary and secondary chambers formed in the inner space of the pump housing, into which the engine oil pumped by the rotation of the rotor respectively flows;
When the pressure of the engine oil is low, the engine oil flows into the primary chamber and the secondary chamber, respectively, while when the pressure of the engine oil is high, the engine oil is supplied to the primary chamber and the secondary chamber, And a bypass valve for discharging the gas from either one of the chambers,
A main oil line connected to the main gallery of the engine and connected to the primary chamber is connected to the secondary chamber to branch the sub oil line to which the engine oil is simultaneously supplied and a bypass oil line having the bypass valve is connected to the secondary Leading to the chamber; The bypass valve cuts off the bypass oil line when the ECU is off, opens the bypass oil line when the ECU is on, and the ECU turns off the bypass valve at a low pressure Off state and switched from a high pressure to an on-pressure (On).
2. The method of claim 1, wherein the low pressure is an engine oil pressure of 2 bar, the high pressure is an engine oil pressure of 4 bar, and the bypass valve is switched from a high pressure to an On Variable oil pump.
2. The apparatus of claim 1, wherein the secondary chamber is located in a camming portion where a variable spring is located, the primary chamber is spaced from the secondary chamber at a location delimited by the cam ring, Wherein the oil pump is installed in the chamber.
delete delete 2. The oil-pressure interlocking type variable oil according to claim 1, wherein the rotor is rotated by a driving force of an engine, and a vane, which is in contact with an inner peripheral surface of a cam ring pushed by a variable spring into the secondary chamber, Pump.

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